AVS 45th International Symposium
    Applied Surface Science Division Wednesday Sessions
       Session AS+BI+SS-WeM

Paper AS+BI+SS-WeM9
Nanometer-Scale Design and Fabrication of Polymer Interfaces using Polydiacetylene Monolayers

Wednesday, November 4, 1998, 11:00 am, Room 307

Session: Organized Molecular Monolayers
Presenter: M.D. Mowery, University of Michigan
Authors: M.D. Mowery, University of Michigan
M. Cai, University of Michigan
H. Menzel, University of Hannover, Germany
C.E. Evans, University of Michigan
Correspondent: Click to Email
The selective control of polymer interfacial characteristics such as viscoelasticity and electronic properties is crucial for numerous important applications from sensor design to device fabrication. In this work, robust interfacial polymer films are successfully fabricated within a single molecular layer with nanometer-scale control of the polymer physical structure. The formation of these unique polymer films is accomplished by the spontaneous assembly of alkyl disulfide precursors containing conjugated diacetylene groups at the gold-solution interface. The resultant well-defined monomer assembly is covalently linked through UV photopolymerization, forming a highly conjugated polymer backbone parallel to the surface. Nanometer-scale control of the interfacial structure is accomplished by manipulating the vertical position of the polymer backbone within the single layer assembly. Additionally, photo-templating affords lateral control over the formation of polymer domains. These subtle variations in physical structure have a profound impact on the global electronic and viscoelastic properties of the polymer interface. The impact of these structural variations is demonstrated by surface infrared and Raman spectroscopy as well as electrochemical capacitance, heterogeneous electron transfer, and reductive desorption measurements. Furthermore, AFM is utilized to physically image the interfacial structure and evaluate the polymer viscoelastic properties. Finally, the application of these monolayer polymers for lithographic applications and the implications for interfacial design are discussed.